Asia-focused hedge funds run by Pine River Capital Management, Segantii Capital Management and Tairen Capital were among those that posted gains in August, when many peers were stung by losses as the region&rsquo;s benchmark stock index had its sharpest decline in more than three years. The $1.2 billion Pine River China Fund returned 1.2 percent in August, while the Segantii Asia-Pacific Equity Multi-strategy Fund rose about 0.8 percent, according to estimates...